Traditionally and most commonly, fastening systems for most athletic shoes consist of a shoelace and a series of eyelets or holes on opposite sides of the instep of the shoe. To put a laced shoo on, a user typically loosens the lace with both hands a series of times until the upper of the shoo is loose enough to insert their foot. To tighten the shoo, the user pulls on the lace with both hands a series of times and subsequently ties a knot near the ends of the lace securing their foot within the shoo and attempting to retain a tight fit. However, the tightness of the fit does not always remain constant as shoelaces subsequently loosen due to the length of the laces and the pressure of each lace section upon the user's foot eventually evening out.
Shoelaces can also become untied forcing a user to interrupt their actions and retie their shoes to prevent tripping or stumbling over the untied laces. To an athlete, tripping or stumbling may have serious consequences. An untied shoelace to a tennis player may result in the loss of an important point; to a basketball player, the loss of a crucial basket; and to a runner, the loss of a race. More importantly, the athlete may fall causing potentially serious injury to themselves and/or others. Even tied shoelaces can extend below the shoe's outsole causing the user to fall or stumble.
Overtightening of a shoelace can cause high pressure points in the instep area greatly impairing the circulation of blood due to the pressure of the lace exerting a large force across a small area. Additionally, some handicapped persons cannot use shoos with shoelaces because it takes two hands to tie the laces. Further, worn shoelaces are susceptible to breakage during the stress applied thereto in the tightening process, and while they are inexpensive to replace, they may break at inopportune times making the shoos unusable unless a spare shoelace is quickly accessible.
Loop and pile element fastening straps, e.g., VELCRO, have been used on shoes in lieu of or in addition to shoelaces as part of shoo fastening systems. These fastening straps consist of two strips of material which produce a relatively strong holding force when interlocked together. Both U.S. Pat. No. D301,935 to Jonah and U.S. Pat. No. D321,084 to Miller et al., illustrate shoe fastening systems including loop and pile fastening straps. In Jonah, two parallel straps extend across the instep of the shoe, and in Miller et al., a first strap extends across the instep of the shoe and a second strap extends around the heel of the shoe. However, loop and pile fastening straps have a disadvantage in that they attract dirt and grime onto their holding surfaces causing their strips to lose its holding power. In addition, a loop and pile fastening strap can become caught or snagged by a surface, potentially unfastening and losing its tensioning power.
A fastening system similar to the type used in some ski boots has been converted for use in a running shoe, and is disclosed in U.S. Pat. No. 5,117,567 to Berger. The shoe has an instep shield, a central tightening lock, a steel wire or wire rope, and guide channels. The central tightening lock is designed to be rotatable with the wire or rope attached to a part thereof. Although this fastening system overcomes many of the problems associated with shoelaces, it tends to be costly to manufacture the central tightening lock and labor intensive to assemble its interface with the shoe. Further, the amount of plastic used for the central tightening lock, the instep shield, and the guide channels increases the weight of the shoe, such that it may not be desirable for an avid runner desiring a lightweight running shoe. Also, the tightening lock and other moving parts can be susceptible to contamination by dirt detrimentally affecting the performance of the fastening system.
Another fastening system utilizes an expandable and contractible bladder within the shoe upper and a small pump and relief valve system attached thereto for controlling the pressure inside the bladder. Although this type of fastening system can help provide a fit with a better pressure distribution, it is costly and is typically used with shoelaces thus containing many of the same disadvantages associated therewith.
Heretofore, many kinds of buckles for fastening or retaining a belt or a strap have been made and used. These buckles typically have a body and a pivotal member attached thereto which is movable between a locked and an unlocked position. In a locked position, a portion of the pivotal member clamps or pinches the strap or belt against a part of the body of the buckle. However, these buckles typically only include one clamping surface which may not be suitable for uses where the reliability of the buckle is an essential quality. As previously discussed, a fastening system on an athletic shoe is one such instance where the loss of shoe tension may be detrimental, possibly causing injury.
U.S. Pat. No. 4,843,688 to Ikeda discloses a belt buckle with a body and a pivotal locking member attached thereto. The body includes a non-sliding bar attached between two opposing sidewalls. The pivotal locking member includes a projection with a non-slip inclined sidewall which interfaces with an apparently smooth sloped surface on the non-sliding bar for frictionally engaging a belt therebetween. The buckle disclosed by Ikeda may be sufficiently reliable for some applications, but in applications where reliable gripping capability is essential, such as use on an athletic shoe, clamping a belt to only one surface of a non-sliding bar, may not be reliable enough.
U.S. Pat. No. 3,328,856 to Jonas discloses a rigid plastic buckle for adjustable shoulder strap assemblies of the kind that are usually employed on women's garments. The body includes a pivotal locking member attached thereto and a non-sliding rectangular bar attached between two opposing sidewalls. The pivotal locking member has a circular concave interior surface or cavity. When the pivotal locking member is in a locked position, the cavity engulfs the non-sliding rectangular bar and frictionally engages the strap only at the four comers of the bar. Hereagain, the buckle disclosed may be sufficiently reliable to hold the forces applied to a strap for some applications, like a shoulder strap of a lightweight women's undergarment, but in applications where reliability is essential, trapping a strap merely at corner points and not between complementary mating surfaces, may not be reliable enough.